US1679316A - Testing equipment for automatic telephone systems - Google Patents
Testing equipment for automatic telephone systems Download PDFInfo
- Publication number
- US1679316A US1679316A US743660A US74366024A US1679316A US 1679316 A US1679316 A US 1679316A US 743660 A US743660 A US 743660A US 74366024 A US74366024 A US 74366024A US 1679316 A US1679316 A US 1679316A
- Authority
- US
- United States
- Prior art keywords
- relay
- circuit
- spring
- test
- conductor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M3/00—Automatic or semi-automatic exchanges
- H04M3/22—Arrangements for supervision, monitoring or testing
- H04M3/26—Arrangements for supervision, monitoring or testing with means for applying test signals or for measuring
- H04M3/28—Automatic routine testing ; Fault testing; Installation testing; Test methods, test equipment or test arrangements therefor
- H04M3/32—Automatic routine testing ; Fault testing; Installation testing; Test methods, test equipment or test arrangements therefor for lines between exchanges
- H04M3/326—Automatic routine testing ; Fault testing; Installation testing; Test methods, test equipment or test arrangements therefor for lines between exchanges for registers and translators
Definitions
- This invention relates in general to' testing equipment for automatic telephone systems, but concerned more particularly with the testing of systems wherein telephone numhere are registered, translated and retransmitted by devices common to a number of trunks.
- a trunk switch seized by the calling subscriber, seizes a translating device; Relays in the trunk switch repeat the impulses from the sub scribers calling device to the mechanisms of the translating device seized.
- the device translatesand retransmits the number over a trunk leading" to a train of automatic switches.
- the translated number may contain either feweig the same, or more digits than the original number, and the digits themselves may be of fewer or more impulses.
- This invention relates specifically to the testing of the trunk switch and translating device.
- I have chosen the socalled director system including the director selector to illustrate my invention although it is equally as well adapted to test any device per-forming the same functions.
- One of the objects of this invention is to test the trunk circuit relays of the director selector to determine if they are in correct adjustment. This is accomplished by impulsing the relays by means of a standard calling device or a varying machine and by extending the impulse circuit so that impulses delivered by the relays operate standard switch mechanisms on the test set.
- the varying machine is arranged to inrpulse relays controlling a switch mechanism at a definite rate of speed over a. high resistance loop, and to again impulse the relays over a short loop which shunted by a low resistance corresponding to a leaky line.
- Switch-through occurs when the director has finished transmitting the digits of the telephone number, and serves to disconnect the director from the trunk and to connect the two ends of the trunk together.
- Still another object of this invention is to- :ipply the above varying test tothe switch mechanism of the director.
- the varying machine impulsesa set of standard relays on the test set which are set in proper adjustment, and the switch mechanisms of the dircctor are adjusted 0 operate as impulses from these relays.
- Figs. 1 and 2 show the circuit arrangements of the test set proper.
- Fig. 3 shows the circuit arrangement of the trunk circuits, director selector, and director.
- V Fig; 4 sliows the structure ofthe register mechanisms 11513-1, inclusive; of Fig. 2.
- Fig; 5 shows a sectional view of indicator hub assembly of the register shown in Fig. 4, taken along the line A-A in the direction of the arrows.
- the director is shown in Fig. 3 only in part forthe reason that it is well known, reference being" made to. the application of ldart-in L. Nelson, Serial No. 7191459, filed June 12, 1924.
- the director is not apart of the present invention, and is not disclosed because it has been ex alained in detail the above application.
- test jacks J and J, and J and J are shown iii F ig". 3.
- the former. Set is located on the director selector bend in one of the trunks leading to the director's.
- Each director is equipped with a pair of jackssuch as J? and J 2 for purposes which will; he hereinafter e'XplaiI'ied.
- twin test lugs P and P are arranged to'beih circuit in either J and J or J Jt.
- Test plilgs TP and TP are arranged to be inserted in either TJ of Fig. 3, or TJ of Fig. 1.
- Test plug TP is conneeted'to the testing mechanism 80 which is shown only in part. This mechanism is the well known varying machine which is explained in detail in the'Patent No. 1,523,030 issued to H. F. Obergfell, on Jan. 15, 1925.
- the manual keys 2-13, inclusive control the circuit from these test plugs to the relays 1519, inclusive, while the calling device 1, which is of the well known type, is operated to send impulses to the director selector.
- the impulse recording mechanism 7 9 may be any one of a number of well known impulse recording mechanisms, such as a printing telegraph device for example.
- relays 1014M, inclusive are the control relays for the switch mechanisms 108 and 109. These mech-- anisms are of the well known type in which the primary movement steps the shaft up elf a row of contacts or levels, and the secondary movement steps the shaft and wipers around to a contact in that level. Magnets 113 and 11 1 control the wiper 170 of the register control switch RC, thereby controlling the registers 115-121, inclusive. Release of the registers is accomplished by means of release key 172 which energizes the series parallel arrangement of release magnets 125-184, inclusive.
- the register mechanism consists of the bracket 500 upon which are mounted the magnets 115 and 125, which operate the armatures 501, 503. to control the indicator 507.
- lilagnet 115 attracts armature 501 which moves pawl 502 into engagement with ratchet 505 to step the indicating arm 50? in a clockwise direction.
- Armature 503 forms a detent which engages the ratchet 505 to hold the indicating arm in its set position.
- the figures on the indi cator are visible through the window 500 of the front plate 508.
- Magnet 125 is energized to release the register. It attracts armature 503, with drawing the detent from theratchet, freeing the indicator arm whichv falls to its normal position against stop 510.
- Fig. 5 is a section view of the hub assembly of the indicator 507 of Fig. 4.
- the ratchet 505 is extended forming a bearing around shaft 515.
- Asscmbledon the ratchet hub are the stop lever 511, spacing washer 512, indicator mounting bracket 506. and spacing washer The assembly is locked to gether by nut 514i and held on the shaft 515 by thejcollar 501.
- the attendant inserts TP of the testing equipment into Til of the trunk circuit relays of the director selector. He then sets the Wipers 4414 11, inclusive, onto the trunk set aside for testing purposes, that trunk being the one which contains'the jacks J and J He then inserts plugs P and P of the test set into jacks J 3 and J", respectively, of the director selector trunks, complet ing a circuit from the test set into the director selector and back into the test set. He then operates key 7 of the test set to arrange the circuit so that the impulses sent out by the testing mechanism 80 are sent in to the pulsing: relay 1-21 of the trunk circuit. The in'lpulses sent by this relay are brought in through the test circuit to operate switch mechanisms 168 or 109, thereby enabling the operator to tell when he has the trunk circuit relay 421 properly adjusted.
- Te restores key 7 to normal and operates key 8, thereby arranging the circuit so that the, impulses sent out by the varying machine will operate the standardly adjuled relay 102 of the test mechanism, which relay impulses the switch mechanism and registers of the director in their proper order.
- the attendant restores key 8 and oper ates key 10 to position A and key '12 which arranges the circuit so that the director im pulses directly into the impulse recording mechanism T0. permitting a check on the. rat in and speed of the impulses sent out by the director.
- the attendant restores the keys 10 and 12 and. reopcrates key 10 to position A aml operatcs key 5 to connect the calling device 1 in circuit with the test set talking relay 102.
- the attendant By rest- I the key 6 to normal, the attendant disconnects pulsing relay 101 and connects in its place relay 102 which he then tests in a similar manner. By operating key13 the attendant may send the impulses sent out by relay 102 to the impulse recordinn mechanism, thereby checking them for impulse ratio and'speed.
- Relay 421 energizes over the above circuit and at spring; 125 closes the circuit to relay 422 which may be traced from ground through relay 422, main spring 425 and its make contact, resistance 42h battery to ground.
- Relay 122 energizes and. at main sprint! 4-20 and make contact 1. res a around on the release trunk con- -r for 116. thereby preventing a line switch from seizing this director selector. The attendant then manually moves wipers 1-il1- e inclusive until the are in connection w n the trunks 194-194' inclusive, re
- Relay 435 energizes and closes its make contacts 136-439, inclusive, extending the trunk coiuluc'tors 4- 15 and 414-8 to the loop of the director.
- the magnet 4&0 does not energize in series with the high resistance relay 435.
- Twin test plug P and P are then inserted in test jacks J a l therel ly connecting the impulsing circuit of the director selector trunk relay to the test set mechanism.
- Key 7 is operated to open the circuit of the release magnet of mechanisms 16S and 169.
- the callingdevice 1 is then operated to alter natcly open and close the circuit of relay 421, thereby causing relay 421 to impulse.
- lVlien relay 4:21 falls back, it opens the circuitof relay 4:22 and immediately applies a short circuit through the winding thereof, which holes relay 122 in an energizedposition for a short time.
- the circuit from ground at the break contact of relay 421, through they make Contact 427, through the make contact d239, through wiper M l and its associated test trunk conductor 197, through the ring contact of jack J and test plug P through main spring 11 and its break contact, through main s n-ingi and its break contact, over conductor 81, tluoi the break contact of spring 12 to spr 3 and its break contact, over conductor 6%., through oil" normal switch spring 156 and its break contact, through relay 106, to vertical magnet- 105 to battery to ;round.
- the switch mechanism 168 may then be released by the operation of key 2, which closes a circuit from ground at make contact of key 2, over conductor 85, make contact the oil normal switch 157, magnet 10? to battery.
- Magnet 107 operates to re lease the switch mechanism, which, upon returning; to normal. opens the oil normal switch contacts 167 thereby opening the cir Relay 121 also closes End cuit to magnet 107.
- key 3 to position A the attendant may cons neet series resistance 69 in series with the loop of relay 121, with the result that relay 121 will deliver a heavy impulse to the switch mechanism 168.
- Switch mechanism 168 is maintained in adjustment so that it will fail on impulses which are heavier than the degree of heaviness set as one of the limits beyond which impulses must be regulated to operate satisfactorily under varying line conditions. It, with resistance 69 in series with the loop, relay 4.21 delivers impulses which are not heavy enough to make switch mechanism 168 fail, the tension of the springs of relay 421 is varied until the impulses are heavy enough to make switch 168 fail.
- the attendant may throw shunt resistance across the loop in parallel with the impulse springs of the calling device, thereby causing impulsing relay 121 to deliver a light impulse.
- the impulse circuit of mechanism 168 is opened, and the impulse circuit from relay 421 is closed to the magnets of mechanism 169.
- This circuit is the same up to the ring conductor of I, from whence it goes to spring 11 and its break contact, spring 9 and its make contact, conductor 56, oil normal switch spring 151 and its break contact, relay 110, and magnet 109 to battery to ground.
- mechanism 169 is identical with that of mechanism 168 except for the fact that mechanism 169 is maintained in such adjustment that it will fail on impulses which are lighter than the degree of lightness set as the other limit beyond which the impulses must be regulated to operate satisfactorily under varying line conditions. It, with resistance 70 in shunt of the impulse springs, relay 421 transmits impulses which are not light enough to cause switch 169 to fail, the springs of relay 421 are adjusted until the impulses are light enough to cause that switch to fail.
- the impulses are then diverted to first one, then the other of switch 168 and 169 by the operation of key 9 and the adjustment of springs of relay 121 varied until the impulses are so regulated that they will be heavy enough with resistance 69 in series with the loop to cause switch 168 to fail and light enough with resistance 70 in shunt of the impulse springs to cause switch 169 to fail.
- Mechanism 169 may then be released by operation of key 2, which closes a circuit from ground to the make springs of key 2.
- conductor 85. conductor 1419. oil normal spring 155 and its make contact, magnet 112 to ground to battery. Magnet 112 operates to release the mechanism, which upon returning to normal opens the oil normal switch spring 155.
- relay 161 which is traced from ground to the lower winding of relay 161, conductor @148, spring +133 and the break contact, main spring 137 and its make contact, wiper 14-2 and its associated test trunk conductor 495, the ring of jack J and test plug 1, spring 32 and its break contact, conductor 66, spring 26 and its make contact, conductor 75, through the lower winding of relay 1?
- Relay M31 and relay 17 energize over the above circuit.
- Relay 17 upon energizing, closes a circuit from ground through make contact 4-3 to the coil of relay 16 to battery to ground.
- Relay 16 energizes and closes the circuit from ground through the make contact of spring through spring 42 and its make contact, conductor 81, to the break contact of spring 9, to the break contact of spring 11 to the ring conductor of the test plug P and the test jack J, conductor 49?, wiper *1-11.
- Relay 17, upon energizing, also closes a circuit from ground through make contact 83 through signal 84 to battery, lighting the signal 84.
- Relay 423 upon energizing, opens the previously defined paths of relays 421 and 461, switching through test jack conductors 115 and 417 directly to the relay 461 and opening the circuit just described for relay 17. Relay 17 falls back immediately extinguishing lamp 8 1. The momentary flash of the signal 84 notifies the attendant that the switch-through was successfully accomplished.
- relay 421 It is necessary to frequently vary relay 421 with the standard varying machine 80. To do this the attendant removes the test plug TP from the test jack T, 1 and inserts in its place test plug TF thereby connecting the varying machine through the pulsing relay 121 of the trunk circuit. By manipulation of the keys K, K and K of the varying machine 80, the attendant may operate the relay 421 over a long loop and over a shunted line.
- the details of the operation of the varying machine 80 are well known, being disclosed in full in the Patent 1,523,036 granted to Herbert F. Ohergfell, on Jan. 13, 1925.
- the impulses set up by relay 421 are conducted over the above described circuit to operate switch mechanisms 168 and 169 of the test set.
- the pulsing relay 421 can, by operating key 11 to the B position, divert those impulses to the impulse recording mechanism 79, over the circuit traceable from ground to the break contact and relay 421, make spring 427, spring tee and its make contact, wiper ⁇ 1 11 and its associated test trunk conductor 497, through the ring of jack J and plug P main spring 11 and its make contact, conductor 7 8, through the impulse recording mechanism 7 9 to grounded battery.
- the operation of key 11 also closes a circuit from ground through spring 31 and its make contact, conductor 77 to mechanism 79. This ground starts the mechanism preparatory to recording the impulses received on conductor 78.
- Relay 811 upon energizing, shunts itself out at spring 812 and its make contact, and, after an interval, falls back, breaking contact of spring v812 and opening the impulsing spring 813.
- relay 811 When relay 811 is shunted out, 810 energizes to control the sender switch as explained in the above application. This operation continues at a definite rate of speed as longjas spring 837 maintains the circuit closed.
- the attendant inserts the test plug Tl into TJ of the test set, closing the circuit from ground through the lower winding of relay 102, conductor 4-9, spring and its break contact, conductor through theftest jack and plug to con- (lHCtOl 66, through the varying machine 80, conductor 61, through the test plug and jack to conductor 68, spring22 and its break conconductor-. 17 to the upper coil. of relay to battery and ground.
- Relay 102 eneres and closes a circuit from grounded "ery to resistance 171, spring 162 and its contact to relay 164C.
- Relay 104 eners and further prepares the impulsing t
- the attendant may. impulse relay 102 with either a light or heavyimpulse.
- relay 102 falls back during the iinpulsing, it closes a circuit from ground through spring 162 and its break contact, s ring 160 and its make contact, conductor break contact conductor 65, spring 40 and its make co ct, conductor 6i, spring 9 and its break contact, spring 11 and its break contact, through the ring P and the jack J conductor 452, through relay 702, wiper arm 719 and its first contact, to mag net- 909 to battery to ground.
- Relay 702 energizes overthe above circuit and remains in an energized position during the impulsing, because of the slug on the heel end ol the core. liiagnet 909 energizes and falls back with the impulses, stepping up the switch mechanism one step for each impulse.
- ll hen relay 102 falls back the .circuit of relay 104: is opened and short circuited at spring 162 and its break contact. However, "may 10-l is adjusted to remain in an energized position during the impulsing, being .eld up by its short circuited winding. As relay 102 is falling back a circuit is momentarily closed from ground through spring 162 and its break contact, spring 161 and'its make contact, conductor 52. springll and its make contact, through the upper winding of relay 17 to battery to ground. Howo9, spring 35 and its ever, relay 1? is so adjusted that it does not respond to such short impulses and remains deenergized.
- relay 702 deencrgizes and closes circuits which move the wiper 719 from a first to a second position, thereby preparing a circuit to magnet 910 so that the second set of impulses operates the latter magnet to rotate the switch mechanism of the director.
- These circuits are not shown in Fig. 3, but are explained in detail in the above application.
- the magnets of the digit register are each operated in turn over the circuit closed by wiper 719 which is controlled in the manner just described.
- the attendant restores key to its normal position which releases the relay 806 and restores the director in the manner explained in detail in the reference of record.
- the attendant repeats the impulsing and release operation on light and heavy impulses from the varying machine until the switch mechanism and registers of the director are found to be in proper adjustment.
- the attendant operates key 10 to position B closing a circuit from ground through spring 30 and its make contact, the sleeve conductor of plug P and jack J conductor 863, to the director start relay which is not shown.
- This start relay operates to remove the short circuit from the loop at spring 854 and its break contact.
- the operation of key 10 also closes a circuit from ground through spring 29 and its make contact, the tip of plug P and jack J to relay 806 to battery, energizing relay 806 to start impulsing relay 811 as previously explained.
- key 12 closes a circuit from the impulse reording mechanism 79 over conductor 77, spring 32 and its make contact, the ring of plug P and jack J conductor 450, through the impulse spring 813, conductor 4 19, to the tip of jack J and plug P spring 33 and its make contact, conductor 78 to the 1mpulse recording mechanism.
- Springs @313 impulse this circuit continuously.
- the 1mpulses may be studied from the record of mechanism 79.
- Relay energizes upon the operation of key 10 as has already been explained.
- Relay 15 upon energizing, closes the circuit of relay 101, which may be traced from ground, through the upper winding of relay 101, conductor 51, spring 87 and its break contact, conductor 723, spring 33 and its make contact, the tip of plug P and jack J conductor 449, impulsing springs 813,
- Relay 101 energizes and at spring 100 and its make contact closes a circuit from ground through the winding of relay 103 to battery, and at spring 163 opens the impulse circuit.
- Relay 103 energizes and at spring 104. prepares the impulse circuit which will be explained later.
- key 5 closes a circuit from ground through the lower winding of relay 102, conductor -19, spring 23 and its break contact, spring and its make contact, normally closed contact to key 1, conductor 72, through the impulse control springs of the calling device 1, conductor 71, through the break contacts of key 3", conductor 82, through spring 21 and its make contact, through spring 22 and its break contact, conductor through the upper coil of relay 102, to negative battery to ground.
- Relay 102 energizes and closes the circuit to relay 101, as has been previously described.
- the calling device 1 is operated impulse springs open and close the circuit of relay 102 causing it to impulse over the impulse circuit to the director, as has also been previously described.
- Relay 101 falls back with each impulse and closes the circuit from ground to spring 39 and its make contact, spring 21 and its break contact, conductor 50, spring 163 and its break contact, spring 101 and its make contact, conductor 55, spring 9 and its break contact, spring 11 and its break con tact, through relay 18 to battery to ground, and also over conductor 67, wiper 170, conductor 137, magnet to battery.
- Relay 1% energizes over the above circuit and remains in an operated position thrmighout the i111- pulsing because of the slug on the heelv end of the core.
- Magnet 115 follows the impulsing, advancing its register in accordance with the first digit sent out by the director.
- relay 101 falls back, it also opens the circuit of relay 103 at springs 100.
- relay 103 is a slow to release relay and remains in operated position during the impulsing.
- Relay 18 upon energizing, closes a circuit, ground through spring 44 and its make contact, through the coil of relay 19 to battery.
- Relay 19 energizes and at spring 4:) prepares the circuit to the register control magnet 113. The circuit, however, is held open at spring 4 1 by relay 18. ⁇ Vhcn the director has finished sending the first digit of the translated telephone number, spring 850 ion closes with its make contact and shunts, out the impulsing springs 813 as is explained in the application of reference.
- Relay 101 comes to restenergized, and at 163 opens the circuit oi.
- relay 18 which falls back after a brief interval, opening the circuit of relay 19 and closing the circuit from ground through spring 44 and its break contact, spring 45 and its make contact, conductor: 58, through magnet 113 to battery.
- hlagnet 113 energizes and advances the wipers 170 to the second contact in connection with conductor 13S and magnet 116.
- .Relay 10 which remained operated for a briet' timc after its circuit was opened because of the copper slug on the heel end of the core, finally falls back and at spring 45 opens the circuit ust traced to ,inagnct 11 3.
- the sec-- ond digitsent out by the dire r is there-- fore registered on the second register by megnet 116, the performance being the some as just described.
- the number which the director has sent out is new registered on the test setregisters 115424, inclusive, and may be read directly oil of these registers.
- the attendant operates key 172 WVlllC-ll closes a circuit from ground, through the make contact of key 172, conductor 136, to register release magnets 125 and 126 to battery, also to relays 127 and 128 in series to battery, and so on through the series parallel arrangement of the register release magnets.
- the director is released by restoring the key to normal.
- Key 10 at spring 27 interrupts the previously described circuit for relay 15, which falls back, and at springs 36 and .37 interrupts the previously traced circuit for relay 101.
- Relay 101 restoresand at sprmg 166 opens the circuit of relay 103 which restores after a brief interval, and at springs 167 and 164 prepares the release circuit for the release magnet 114 oftheregister control BC.
- the register control is then restored to normal by operating the dial release key 4 which opens the previously traced circuit of relay 102, which falls back closing the circuit traceable from ground, through spring 162 and its break contact, through spring 160 and its break contact, relay 104 having fallen back when its circuit was opened at relay 162 as previously explained, conductor 53, through spring 39 and its break contact, through spring 24 and its break contact, over conductor 50, through spring 163 and its break contact, through spring 164 and break'contact, through springs 167, over conductor 148, through springs 165, through the winding of release magnet 114 to grounded negative battery.
- the registers and reg ister control 01" the testing equipment and the registers of the director are then all returned to normal, ready .to check the next number which ,is set up by the calling
- he pulsing relay 102 and the switch mechanisms 168 and 169 of the test set are used as standards against which the pulsing relays and mechanisms of the director selector and director are checked. It is therefore-necessary that these pieces of testing equipment should be frequently tested to make sure that their adjustment is standard.
- the attendant inserts TP into test jack TJ and operates keys 6 and'lO to position A and key 9to position A. Circuits are then completed from ground through spring 27 and its make contact, conductor 7 6, through the coil of relay to grounded battery.
- Relay 15 operates and prepares the impulsing circuit which will be hereinafter explained.
- a circuit is also closed from ground to the upper winding of relay 101, conductor 51, spring 23 and its make contact, conductor 67, through the test jack and plug to conductor 60, through the varying machine to conductor 61, through the testplug and jack to. conductor 68, spring 22 and its make contact, conductor 48, throughthe lower winding of relay 101 to battery.
- pul ing relay 101 can be made to pulse with light or heavy impulses.
- the pulsing circuit of relay 101 may be traced from ground through spring 89 and its make contact, spring 24 and its break contact, conductor 550, spring 163 and its break contact, spring and its make contact, conductor 55,
- Relay 101 pulsing over the above circuit operates mechanism 168 in the well known manner explaincd hereinbet'ore. T impulse the mechanism 169, the attendant restores key to normal thereby releasing relay which restores, and operates key 11 to position A. The impulsing circuit of relay 101 is then traced from ground to spring 162 and its break contact, spring 160 and its break contact, conductor 53, spring 39 and its break contact, spring 24. and its break contact, conductor 50, spring 163 and its break contact, an and its make contact, conductor 55, spring 9- and its break contact, spring 11 and its make contact, conductor 56,
- Switch mechanism 169 then operates in the well known manner.
- the attendant restores key 6 to normal, thereby connecting the relay to the varying machine 80 over a circuit which has been previously traced; and by operating key 13 diverts the impulses into the impulse recording mechanism 79 over a circuit which may be traced from ground through spring 162 and its break contact, spring and its make contact, conductor 59, spring 35 and its make contact, conductor 78, to groimded battery in the impulse recording mechanism 79.
- the attendant connects the pulsing relay 101 to the varying machine in the manner just described, restores key 9 and key 11 to normal, operates key 10 to position A to close the previously described circuit to relay 15 thereby completing the pulsing circuit of relay 101 which may now be traced from ground through make contact 39, to break contact of key 7, conductor 50, spring 163 and its break contact, spring 18-1 and its make contact, conductor 55, spring 9 and its break contact, spring 88 and its break contact, through relay 18 to ground and battery, and also over conductor 57 through wiper and its first contact, conductor 137, through magnet 115 to battery.
- Relays 18 and 19 and magnet 115 function in the manner previously described to set up the registers 115-424, inclusive, in order from the, impulses of relay 101.
- a telephone exchange a plurality of trunk circuits containing relays, a plurality of digit translating devices common to said trunk circuits, a testing mechanism, means for connecting said testing mechanism to said trunk circuits, means for connecting said trunk circu ts with one of said translatinc devices. and. means tor disconnecting the connected translating device and subst tuting the test mechanisn'l therefor.
- a plurality of trunk circuit-s containing relay a plurality ol 'l,ran1 'lating devices common to said trunk circu'ts, means for associating one oi said devices with a trunk circuit, testing mechanism, means for associating said test mechanism with the input and output circuits f said trunk circuits and for dissociating sa d translating device therefrom, means in said test mechanism for transmitting impulses to the relays of said trunk circuit under varying conditions, and means in the test mechan'sm responsive to impulses of direct current transmitted by said trunk circuit rclavs.
- a test n'iechanism containing; two switch mechanisms,one adjusted to operate on a light impulse, the other adjusttal to operate on a heavy impulse, means for associating said test with said trunk circuit relays and for impuls'ng said relays. means for directing the inmulses delivered by said relays to operate one of said switch mechanisiim. and means for disconnecting said switch mechanism and for directing the impulses to the other said switch mechanism.
- a pluralitv ot digit translating devices common to and coutrolled by a plurality of trunk circuits contaming relays, a test mechanism, means for connecting said test meehanisn'i to said translating device in lieu of said trunk circuits. and means in said test mechanism for then controlling said translating device.
- a pluralitv oi translating devices said devices I having means for registering a. telephone number. translating it into fewer or more digits and retransmitting the translated number.
- a test mechanism containing relays and registers. means for a iciatiug said test mechanism with one of said translating devices.
- means 101' causing said test mechanism l'cltlVs: to impulse into said trandatin r device, and means for causing the translated telephone number sent out by said translating device to be intercepted and registered upon said test mechanism registers.
- a pluralitypf translating devices arranged to register, translate and retransmit a telephonenumber and containing an impulsing device, a test mechanism containing a plurality of digit registers associated with, a control switch, means forconncctingsaid test mechanism to anyone of said translating devices, said test mechanism comprising a relay responsive to the impulsesot a' digit sent by said impulsing device for actuating onept' ,said 13egisters, and means acting at, the end of said digit for moving said control switch toassociate saidrelaywith the next register, said relay thereafter operating that register responsive to the impulses of,the :nextdigit sent by the impulsing device.
- a telephone exchange a trunk circuit containing relays, a translating device associated with said-trunk circuit, said trans lating device containing switch mechanism controlled by said trunkcircuit relays, a test mechanism containingrelaysand a plurality of switch mechanisms, means, for connecting saichtest mechanism with, either said trunk circuit or the translating device,means in the test mechanismfor impulsing either said trunkcircuit or test mechanism relay, means in the one instance for directing the impulses deliveredby the trunk circuit relaysto their test set switch mechanismg and means in another instance for directing the impulses delivered by said testset relaysto cause them to operateeither said testswitch mechanism or said translating device. switch mechanism,
- a plurality of trunk circuits containing relays, a plu rality of translating devices common to said trunk circuit, means-for associating oneof said devices with a ,trunlrc-ircuit, testing mechanism, and means forassociating, said test mechanismawith the input and, output circuits of said trunk circuit and for dissociating said translatingdevice therefrom, said means cooperating with said trunk cir cuit relays to render the disassociated translating device unselectable from other trunlc circuits.
- a trunk cir cuit containing relays, a test mechanism containing relays, a plurality of switch mechanisms and an impulse recording device, means for connecting said test mechanism with the input and output circuit of said trunk circuit relays, means in the testing mechanism for impulsing either said trunk circuit or test mechanism relays, means in one instance for directing the impulses from said test mechanism relays to said switch mechanisms, and means in another instance for directing the impulses from said trunk circuit relays to either of the switches of the test mechanisms or to an impulse record in device.
- T311 a telephone exchange, a translating device containing switch mechanisms and ⁇ viththe input and output circuits of said.
- translating device means in the test mechanism for impulsing saidrelays, means for directing the impulses from said relays to operate, said, switch -mech anis1ns of either the testing mechanism or the translating device, and means for directing the impulses from said impulsing device of the translating device either-to the switches of the testing mechanism or to the impulse recording device.
- a translating device having means for registering, trans,- lat-ing and retransmitting a telephone numher, and means for thereafter disconnecting itself, a test mechanism containing relays, registers and a signal, meansfor associating said testing mechanism with the translating device, means for causing said testing mechanism relays to impulseintolsaid translating device, means for intercepting the telephone number sent out by said translating device and registering it upon said testing mechanism registers, and means for operating said signal when said translating device disconnects itself, V
- a trunk circuit In a telephone exchange, a trunk circuit,a translatingdevice, a switch train, means for extending said trunk circuitto said translating device, means for thereafter switchingthrough said trunk circuit to said switch train and disconnecting it fromsaid translating device, a testing mechanism con taining a signal, meansfor associating said testing mechanism with said trunk circuit, means in the testing mechanism for operating said switching through means, and means for flashing said signal if the switching through means operates properly.
- a trunk circuit a translating device, means for connect ing the trunk circuit to the translating device, means in said trunk circuit for lnealring the established connection, means in said translating device for controlling said disconnect means, testing equipment, means for connecting it to either the trunk circuit or the t 'anslating device, means in said testing equipment for controlling said disconnect means of the trunk circuit, means for causing the translating device controlling meanstto function, and means for supervising the operation of the disconnect and controlling means.
- a trunk circuit for translating equipment connected thereto, a relay for disconnecting the two, a device in the translating equipment for operating said relay at a delinite time, testing equipment, said test-ing equipment having access to both the trunk circuit and the translating equipment, means in the testing equipment for causing the operation of said relay or the operation of said device, and means in the testing equipment for indicating the correct or incorrect functioning of said device or relay.
- a trunk circuit having a translating device associated therewith, that translating device having means responsive to digits of acalled number transmitted from the trunk circuit for translating and retransmitting said digits, testing equipment, and means for connecting it to said trunk circuit or translating device, said testing equipment having means for intercepting the impulses delivered either from the trunk circuit or from the translating device and for observingor registering said impulses.
- a trunk circuit having a translating device associated therewith, said translating device having means responsive to digits of a called number trans.- mitted from the trunk circuit for translating and retransmitting said digits, testing equipment, means for connecting it to said trunk circuit or translating device, said testing equipment having means for transmitting impulses of different character ,to the trunk circuit or to the translating device, and having also means for intercepting the impulses delivered either from the trunk circuit or from the translating device and for observing or registering said impulses.
- a trunk circuit including means responsive to impulses from the trunk circuit for translating and retransmitting the digits of a called number
- testing equipment including impulse transmitting devices, impulse recording devices and switch mechanism, means for connecting the testing equipment either with the trunk circuit or the translating device. and a set of keys in the testing equipment certain of which connect the transmitting devices with either the trunk circuit or the t'anslating device and others of which connect the impulse recorder or the switch mechanism with either the trunk circuit or the translating device.
- a plurality of trunk circuits containing relays, a plurality of translating devices, common to and select able by said trunk circuits, means for associating one of said devices with a trunk circuit, testing mechanism, means for associat ing said testing mechanism with ,the input and output circuits of said trunk circuits, and for dis-associating said translating device therefrom, said means cooperating with said .trunk circuit relays to render said disassociated translating device unselectable by other trunk circuits, means in said test mechanism fortransmitting impulses to the relays of said trunk circuit under varying conditions, and means in the test mechanism responsive to impulses transmitted by said trunk circuit relays.
- a plurality of trunk circuits containing relays containing relays
- a test mechanism containing a plurality of devices each adjusted to operate on different types of impulses
- means for associating said test mechanism with said trunk circuit relays and for impulsing said relays means for directing the impulses delivered by said relays to operate said devices.
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Sub-Exchange Stations And Push- Button Telephones (AREA)
- Monitoring And Testing Of Exchanges (AREA)
Description
July 31 1928. 1,679,316
F. T. MADSEN TESTING EQUIPMENT FOR AUTOMATIC TELEPHONE SYSTEMS Original Filed Oct. 15, 1924 4 Sheets-Sheet l Frsd T Wadsen F. T. MADSEN TESTING EQUIPMENT FOR AUTOMATIC TELEPHONE sYs'rBus July 31, 1928.
ori inal Filed Oct. 15, 1924 mm I Aw mwrmm wwmm 8% s3 --In"u5'n' Tip- Fred T PTadsen July 31, 1928.
Original Filed Oct. 15, 1924 F. 'r. MADSEN TESTING EQUIH'ENT FOR AUTOMATIC TELEPHONKSISTEIS 4 Sheets-Sheet 3 -Inusn DP- July 31,. 1928.
F. T. MAD$EN TESTiNG EQUIPMENT FOR AUTOMATIC TELEPHONE SYSTEMS Original Filed Oct! 15, 1924 4 Sheets-Sheet 4 Fred TFIadssn Patented July 31,- 1928.
UNITED STATES PATENT OFFICE.
FRED'T. Ans'E v, or EoE-EsT' I -AE K, ILLINOIS, iissIen-en BY MESNE AssI'GN-MENTs;
To AUTOMATIC ELECTRIC me, or CHICAGO, ILLINOIS, A CORPORATION 0E DELA- WARE.
TESTING EQUIPMENT FOR AUTOMATIC TELEPHONE SYSTEMS.
,A iication filed October 15, 1924, Serial m. 7431660; Renewed m 28, 192?.
This invention relates in general to' testing equipment for automatic telephone systems, but concerned more particularly with the testing of systems wherein telephone numhere are registered, translated and retransmitted by devices common to a number of trunks. In such a system a trunk switch, seized by the calling subscriber, seizes a translating device; Relays in the trunk switch repeat the impulses from the sub scribers calling device to the mechanisms of the translating device seized. The device translatesand retransmits the number over a trunk leading" to a train of automatic switches. The translated numbermay contain either feweig the same, or more digits than the original number, and the digits themselves may be of fewer or more impulses. w V
This invention relates specifically to the testing of the trunk switch and translating device. I have chosen the socalled director system including the director selector to illustrate my invention although it is equally as well adapted to test any device per-forming the same functions.
One of the objects of this invention is to test the trunk circuit relays of the director selector to determine if they are in correct adjustment. This is accomplished by impulsing the relays by means of a standard calling device or a varying machine and by extending the impulse circuit so that impulses delivered by the relays operate standard switch mechanisms on the test set.
The varying machine is arranged to inrpulse relays controlling a switch mechanism at a definite rate of speed over a. high resistance loop, and to again impulse the relays over a short loop which shunted by a low resistance corresponding to a leaky line.
Another object is to test the switch through function of the director selector. Switch-through occurs when the director has finished transmitting the digits of the telephone number, and serves to disconnect the director from the trunk and to connect the two ends of the trunk together. 7
Still another object of this invention is to- :ipply the above varying test tothe switch mechanism of the director. The varying machine impulsesa set of standard relays on the test set which are set in proper adjustment, and the switch mechanisms of the dircctor are adjusted 0 operate as impulses from these relays. v
Afurther object is to determine if theimpulses sent out by the director are of the proper ratio of make and break and if they are sent out the correct speed; 'Another' object of this invention is to determine if the director sends out the proper digits. A certain number is dialled into the director and thetranslated Iiiimber which the director sends out is intercepted and recorded on the test set register, sot-hat its accuracy may be checked.
A still further object to provide a aircuit arrangementwhereby the imulse re lays and the switch mechanisms 0' the test set itself may be checked to determine if they are in proper adjustment,
ilhereare several other objects and tea tu'res of this invention which eanbe understood best from a pe1'iisa l".oftl1e detailed description which is to follow.
Referring to the drawings, Figs. 1 and 2 show the circuit arrangements of the test set proper.
' ,Fig. 3 shows the circuit arrangement of the trunk circuits, director selector, and director.
V Fig; 4 sliows the structure ofthe register mechanisms 11513-1, inclusive; of Fig. 2.
Fig; 5 shows a sectional view of indicator hub assembly of the register shown in Fig. 4, taken along the line A-A in the direction of the arrows.
The director is shown in Fig. 3 only in part forthe reason that it is well known, reference being" made to. the application of ldart-in L. Nelson, Serial No. 7191459, filed June 12, 1924. The director is not apart of the present invention, and is not disclosed because it has been ex alained in detail the above application.
Two sets of test jacks J and J, and J and J are shown iii F ig". 3. I The former. Set is located on the director selector bend in one of the trunks leading to the director's. Each director is equipped with a pair of jackssuch as J? and J 2 for purposes which will; he hereinafter e'XplaiI'ied.
Referring to Fig, 1, twin test lugs P and P are arranged to'beih circuit in either J and J or J Jt. Test plilgs TP and TP are arranged to be inserted in either TJ of Fig. 3, or TJ of Fig. 1. Test plug TP is conneeted'to the testing mechanism 80 which is shown only in part. This mechanism is the well known varying machine which is explained in detail in the'Patent No. 1,523,030 issued to H. F. Obergfell, on Jan. 15, 1925.
The manual keys 2-13, inclusive, control the circuit from these test plugs to the relays 1519, inclusive, while the calling device 1, which is of the well known type, is operated to send impulses to the director selector.
Referring again to Fig. 1. the impulse recording mechanism 7 9 may be any one of a number of well known impulse recording mechanisms, such as a printing telegraph device for example. Referring to Fig. 2, relays 1014M, inclusive, are the control relays for the switch mechanisms 108 and 109. These mech-- anisms are of the well known type in which the primary movement steps the shaft up elf a row of contacts or levels, and the secondary movement steps the shaft and wipers around to a contact in that level. Magnets 113 and 11 1 control the wiper 170 of the register control switch RC, thereby controlling the registers 115-121, inclusive. Release of the registers is accomplished by means of release key 172 which energizes the series parallel arrangement of release magnets 125-184, inclusive.
Referring to Fig. 4, the register mechanism consists of the bracket 500 upon which are mounted the magnets 115 and 125, which operate the armatures 501, 503. to control the indicator 507. lilagnet 115 attracts armature 501 which moves pawl 502 into engagement with ratchet 505 to step the indicating arm 50? in a clockwise direction. Armature 503 forms a detent which engages the ratchet 505 to hold the indicating arm in its set position. The figures on the indi cator are visible through the window 500 of the front plate 508.
Fig. 5 is a section view of the hub assembly of the indicator 507 of Fig. 4. The ratchet 505 is extended forming a bearing around shaft 515. Asscmbledon the ratchet hub are the stop lever 511, spacing washer 512, indicator mounting bracket 506. and spacing washer The assembly is locked to gether by nut 514i and held on the shaft 515 by thejcollar 501.
To execute one of the objects of this invention, that is, the varying of the director selector trunk relay, the attendant inserts TP of the testing equipment into Til of the trunk circuit relays of the director selector. He then sets the Wipers 4414 11, inclusive, onto the trunk set aside for testing purposes, that trunk being the one which contains'the jacks J and J He then inserts plugs P and P of the test set into jacks J 3 and J", respectively, of the director selector trunks, complet ing a circuit from the test set into the director selector and back into the test set. He then operates key 7 of the test set to arrange the circuit so that the impulses sent out by the testing mechanism 80 are sent in to the pulsing: relay 1-21 of the trunk circuit. The in'lpulses sent by this relay are brought in through the test circuit to operate switch mechanisms 168 or 109, thereby enabling the operator to tell when he has the trunk circuit relay 421 properly adjusted.
hen the attendant has completed, his varying test of the trunk circuit relay, he removes test plug TP from the test jack TJ and inserts in its place test phu. Tl". He then restores key 7 to normal and operates the key 8, arranging the circuits to complete the circuit of relay 423. This relay functions to switch through the trunk circuitrclays of the director selector and to disconnect the director from the trunk, and in so doing causes the test circuit to intermittently light the lamp 84, giving the attendant an indication that the switch-through is completed.
It is necessary that the switch meclumism and registers of the director be kept in adiustn 1 so that they will function properly with the trunk circuit relay 421. To check up on this adjustment the attendant inserts twin plugs P and P in J and J of the. director and inserts T1 of the varying mo.-
chine into the. test jack TJ or the test set.
Te then restores key 7 to normal and operates key 8, thereby arranging the circuit so that the, impulses sent out by the varying machine will operate the standardly adjuled relay 102 of the test mechanism, which relay impulses the switch mechanism and registers of the director in their proper order. After having the mechanism properly adjusted, the attendant restores key 8 and oper ates key 10 to position A and key '12 which arranges the circuit so that the director im pulses directly into the impulse recording mechanism T0. permitting a check on the. rat in and speed of the impulses sent out by the director. The attendant then restores the keys 10 and 12 and. reopcrates key 10 to position A aml operatcs key 5 to connect the calling device 1 in circuit with the test set talking relay 102. He then dials the numher into the register mechanism of the director, which number is translated and sent out over the line circuit of the director to opera to the pulsing relay 101 of the test set. This relay operates the test set registers 11542-1, inclusive, recording thereon the number aeloo Lin
The attendnt ma-y' then read the number sent direoly on the registers of the te t set, and if th y are correct release the re; stcrs by opera non of release key 1'72, and release the director by restoring the key 10.
It easily seen that the standard pulsing relay and switch mechanisms of the test set, by means of which the testing relay of the director selector and switch mechanisms of the director are adjusted, nmst he routincd frequently to see that they are kept in proper adjustment. This is accomplished by ii'isertinu the test plug; of the varying; machine TP int-o TJ and opera-ting key 10 to position, A and key. 6 and key 9 to position A. The circuits are then arranged. so that the standard pulsing relay 101 Will send. impulses to the switch mechanism 108. By restoring key 9 to normal and operating key 11 to position A, the impulses from this pulsing relay 101 will be sent to switch mechanism 169. By rest- I the key 6 to normal, the attendant disconnects pulsing relay 101 and connects in its place relay 102 which he then tests in a similar manner. By operating key13 the attendant may send the impulses sent out by relay 102 to the impulse recordinn mechanism, thereby checking them for impulse ratio and'speed.
Having thus explained my invention n general, I will now explain its operation in detail. To test the director selector for pulsing" the attendant inserts themtest plug TF into the test jack TJ closing a circuit of trunk circuit relay 121 which may be i from around through the lower Wind- T my 421, spring 4133 and its break coiuluetor 4117, contact 491 of the TJ lower line conductor of the test P}, conductor (3 1, spring 21 and s 1) ltand its normal contact, conductor 71 to the impulse sprii'igrs of the calling device 1, conductor 72, through the normally closed contacts of key 4-, to spring 20 and its normal contact, tl'irounh conductor 63, the upper line terminal or testplug TP conductr 490 of the test jack T, to conductor 115 through spring" 4150 and its break cortact, to the upper coil of relay 4-21, to battcry to ground. Relay 421 energizes over the above circuit and at spring; 125 closes the circuit to relay 422 which may be traced from ground through relay 422, main spring 425 and its make contact, resistance 42h battery to ground. Relay 122 energizes and. at main sprint! 4-20 and make contact 1. res a around on the release trunk con- -r for 116. thereby preventing a line switch from seizing this director selector. The attendant then manually moves wipers 1-il1- e inclusive until the are in connection w n the trunks 194-194' inclusive, re
spectively. As this test trunk is idle at the time, there Wlll be no ground potential on bank contact 1 13, and the circuit to 435 will be completed from ground to make spring;
128, relay 135, armature spring and break contact of magnet 410 through magnet 1 10 to battery to ground. Relay 435 energizes and closes its make contacts 136-439, inclusive, extending the trunk coiuluc'tors 4- 15 and 414-8 to the loop of the director. The magnet 4&0 does not energize in series with the high resistance relay 435. Twin test plug P and P are then inserted in test jacks J a l therel ly connecting the impulsing circuit of the director selector trunk relay to the test set mechanism. Key 7 is operated to open the circuit of the release magnet of mechanisms 16S and 169. The callingdevice 1 is then operated to alter natcly open and close the circuit of relay 421, thereby causing relay 421 to impulse. lVlien relay 4:21 falls back, it opens the circuitof relay 4:22 and immediately applies a short circuit through the winding thereof, which holes relay 122 in an energizedposition for a short time. the circuit from ground at the break contact of relay 421, through they make Contact 427, through the make contact d239, through wiper M l and its associated test trunk conductor 197, through the ring contact of jack J and test plug P through main spring 11 and its break contact, through main s n-ingi and its break contact, over conductor 81, tluoi the break contact of spring 12 to spr 3 and its break contact, over conductor 6%., through oil" normal switch spring 156 and its break contact, through relay 106, to vertical magnet- 105 to battery to ;round. clay 106. and Vertical magnet energize over the above traced circuit. Magnet 105 ad vances thesl'iait one step, closingoll' normal springs so that the renuiining impulses go through s u-iug 1:30 and its make contact, spring 159 and its make contact, through relay 100, magnet to battery. Relay 106,
being slow to rclease,-rcmains in an open end oi the series of impulsesrelay 106 as energizes, changing the circuit at spring 150 so that the next train of impulses will operate rotary magnet 108 instead of vertical magnet 105.
The switch mechanism 168 may then be released by the operation of key 2, which closes a circuit from ground at make contact of key 2, over conductor 85, make contact the oil normal switch 157, magnet 10? to battery. Magnet 107 operates to re lease the switch mechanism, which, upon returning; to normal. opens the oil normal switch contacts 167 thereby opening the cir Relay 121 also closes End cuit to magnet 107. By the operation of key 3 to position A the attendant may cons neet series resistance 69 in series with the loop of relay 121, with the result that relay 121 will deliver a heavy impulse to the switch mechanism 168. Switch mechanism 168 is maintained in adjustment so that it will fail on impulses which are heavier than the degree of heaviness set as one of the limits beyond which impulses must be regulated to operate satisfactorily under varying line conditions. It, with resistance 69 in series with the loop, relay 4.21 delivers impulses which are not heavy enough to make switch mechanism 168 fail, the tension of the springs of relay 421 is varied until the impulses are heavy enough to make switch 168 fail.
By throwing key 3 to position B, the attendant may throw shunt resistance across the loop in parallel with the impulse springs of the calling device, thereby causing impulsing relay 121 to deliver a light impulse. By operating key 9 to position 15 the impulse circuit of mechanism 168 is opened, and the impulse circuit from relay 421 is closed to the magnets of mechanism 169. This circuit is the same up to the ring conductor of I, from whence it goes to spring 11 and its break contact, spring 9 and its make contact, conductor 56, oil normal switch spring 151 and its break contact, relay 110, and magnet 109 to battery to ground. The operation of mechanism 169 is identical with that of mechanism 168 except for the fact that mechanism 169 is maintained in such adjustment that it will fail on impulses which are lighter than the degree of lightness set as the other limit beyond which the impulses must be regulated to operate satisfactorily under varying line conditions. It, with resistance 70 in shunt of the impulse springs, relay 421 transmits impulses which are not light enough to cause switch 169 to fail, the springs of relay 421 are adjusted until the impulses are light enough to cause that switch to fail.
The impulses are then diverted to first one, then the other of switch 168 and 169 by the operation of key 9 and the adjustment of springs of relay 121 varied until the impulses are so regulated that they will be heavy enough with resistance 69 in series with the loop to cause switch 168 to fail and light enough with resistance 70 in shunt of the impulse springs to cause switch 169 to fail.
Mechanism 169 may then be released by operation of key 2, which closes a circuit from ground to the make springs of key 2. conductor 85. conductor 1419. oil normal spring 155 and its make contact, magnet 112 to ground to battery. Magnet 112 operates to release the mechanism, which upon returning to normal opens the oil normal switch spring 155.
ll-laving completed the adjustment of relay 421 the attendant may then test the director selector switch-through by I'OSlZOP-f ing keys 3 and 9 to normal, and operating key S. The operation of key 8 closes the circuit of relay 161, which is traced from ground to the lower winding of relay 161, conductor @148, spring +133 and the break contact, main spring 137 and its make contact, wiper 14-2 and its associated test trunk conductor 495, the ring of jack J and test plug 1, spring 32 and its break contact, conductor 66, spring 26 and its make contact, conductor 75, through the lower winding of relay 1? to conductor 73, spring 33 and its break contact, to the tip of plug P and ark J, conductor 194, wiper 4 11, make contact 136, conductor at?) to the upper coil of relay 461 to battery to ground. Relay M31 and relay 17 energize over the above circuit.
Relay 17, upon energizing, closes a circuit from ground through make contact 4-3 to the coil of relay 16 to battery to ground. Relay 16 energizes and closes the circuit from ground through the make contact of spring through spring 42 and its make contact, conductor 81, to the break contact of spring 9, to the break contact of spring 11 to the ring conductor of the test plug P and the test jack J, conductor 49?, wiper *1-11. make contact 139, make contact 427, make contact of relay 421, to relay 42 to battery to ground. Relay 17, upon energizing, also closes a circuit from ground through make contact 83 through signal 84 to battery, lighting the signal 84.
It is necessary to frequently vary relay 421 with the standard varying machine 80. To do this the attendant removes the test plug TP from the test jack T, 1 and inserts in its place test plug TF thereby connecting the varying machine through the pulsing relay 121 of the trunk circuit. By manipulation of the keys K, K and K of the varying machine 80, the attendant may operate the relay 421 over a long loop and over a shunted line. The details of the operation of the varying machine 80 are well known, being disclosed in full in the Patent 1,523,036 granted to Herbert F. Ohergfell, on Jan. 13, 1925. The impulses set up by relay 421 are conducted over the above described circuit to operate switch mechanisms 168 and 169 of the test set.
If, for any reason, the attendant ucsircs to know exactly what kind of an impulse the pulsing relay 421 is delivering he can, by operating key 11 to the B position, divert those impulses to the impulse recording mechanism 79, over the circuit traceable from ground to the break contact and relay 421, make spring 427, spring tee and its make contact, wiper {1 11 and its associated test trunk conductor 497, through the ring of jack J and plug P main spring 11 and its make contact, conductor 7 8, through the impulse recording mechanism 7 9 to grounded battery. The operation of key 11 also closes a circuit from ground through spring 31 and its make contact, conductor 77 to mechanism 79. This ground starts the mechanism preparatory to recording the impulses received on conductor 78.
hen the directors are to be tested, it is necessary that they be temporarily put out of commission and made busy so that the director selectors cannot seize them. This is accomplished by operating locking key P which places ground on-the private conductor 481 through thebreak contacts of jack J to conductor 496, through the banks of the director selector, over which wiper 443 rotates. The presence of ground on this bank contact preyents any director selector from stopping on the contact. The attendant then blocks the dead code relay 902 in a normal position to prevent the di rector from sending the dead code number in case'such a code is called during the director test. This relay is not shown in Fig. 3, but is shown in detail and explained in the application of h'la-rtin L. Nelson. Seri al No. 719,459, filed June 12, 19%. The attendant then plugs relay 810 in its operated position, thereby opening the circuit to the sender control switch of the director, which switch is not shown in this drawing but is explained in the above application. Twin test plugs P and P are next inserted in the director test jacks J and J and manual key 10 of the test set operated to its A position with all the other keys restored to normal. The circuit is then closed from ground, spring 28 and its make contact, the tip of plug P and jack J through relay 806 to battery. Relay 806 energizes and at spring 887 and make contact closes the circuit from ground through relays 811 and 810 in series to battery. Relay 810 does not energize in series with the high resistance of relay 811. Relay 811, upon energizing, shunts itself out at spring 812 and its make contact, and, after an interval, falls back, breaking contact of spring v812 and opening the impulsing spring 813. When relay 811 is shunted out, 810 energizes to control the sender switch as explained in the above application. This operation continues at a definite rate of speed as longjas spring 837 maintains the circuit closed.
The operation of key to position A also closes a circuit from ground through spring 2? and its makecontact,conductor 76-t0re lay to battery and ground. Relay l5 energizes over this circuit and preparesthe impulsing circuit, which will be explained hereafter. The impulsing of the loop by spring 813 is without effect at this time because of the short heldon the .loopby spring 85% and its break contacts, which arein multiple with spring 813.
To vary the switch mechanisms and registers of the director,the attendant inserts the test plug Tl into TJ of the test set, closing the circuit from ground through the lower winding of relay 102, conductor 4-9, spring and its break contact, conductor through theftest jack and plug to con- (lHCtOl 66, through the varying machine 80, conductor 61, through the test plug and jack to conductor 68, spring22 and its break conconductor-. 17 to the upper coil. of relay to battery and ground. Relay 102 eneres and closes a circuit from grounded "ery to resistance 171, spring 162 and its contact to relay 164C. Relay 104: eners and further prepares the impulsing t By manipulation of keys K and the varying machine 80, the attendant may. impulse relay 102 with either a light or heavyimpulse. When relay 102 falls back during the iinpulsing, it closes a circuit from ground through spring 162 and its break contact, s ring 160 and its make contact, conductor break contact conductor 65, spring 40 and its make co ct, conductor 6i, spring 9 and its break contact, spring 11 and its break contact, through the ring P and the jack J conductor 452, through relay 702, wiper arm 719 and its first contact, to mag net- 909 to battery to ground. Relay 702 energizes overthe above circuit and remains in an energized position during the impulsing, because of the slug on the heel end ol the core. liiagnet 909 energizes and falls back with the impulses, stepping up the switch mechanism one step for each impulse. ll hen relay 102 falls back the .circuit of relay 104: is opened and short circuited at spring 162 and its break contact. However, "may 10-l is adjusted to remain in an energized position during the impulsing, being .eld up by its short circuited winding. As relay 102 is falling back a circuit is momentarily closed from ground through spring 162 and its break contact, spring 161 and'its make contact, conductor 52. springll and its make contact, through the upper winding of relay 17 to battery to ground. Howo9, spring 35 and its ever, relay 1? is so adjusted that it does not respond to such short impulses and remains deenergized.
At the end of the first series of impulses, relay 702 deencrgizes and closes circuits which move the wiper 719 from a first to a second position, thereby preparing a circuit to magnet 910 so that the second set of impulses operates the latter magnet to rotate the switch mechanism of the director. These circuits are not shown in Fig. 3, but are explained in detail in the above application. The magnets of the digit register are each operated in turn over the circuit closed by wiper 719 which is controlled in the manner just described.
To release the switch mechanisms and registers of the director, the attendant restores key to its normal position which releases the relay 806 and restores the director in the manner explained in detail in the reference of record. The attendant repeats the impulsing and release operation on light and heavy impulses from the varying machine until the switch mechanism and registers of the director are found to be in proper adjustment.
To test the impulses sent out by the impulsing spring 813 of the director, the attendant operates key 10 to position B closing a circuit from ground through spring 30 and its make contact, the sleeve conductor of plug P and jack J conductor 863, to the director start relay which is not shown. This start relay operates to remove the short circuit from the loop at spring 854 and its break contact. The operation of key 10 also closes a circuit from ground through spring 29 and its make contact, the tip of plug P and jack J to relay 806 to battery, energizing relay 806 to start impulsing relay 811 as previously explained. The operation of key 12 closes a circuit from the impulse reording mechanism 79 over conductor 77, spring 32 and its make contact, the ring of plug P and jack J conductor 450, through the impulse spring 813, conductor 4 19, to the tip of jack J and plug P spring 33 and its make contact, conductor 78 to the 1mpulse recording mechanism. Springs @313 impulse this circuit continuously. The 1mpulses may be studied from the record of mechanism 79.
To test the director for sending the proper digits, the attendant operates key 10 to position A and operates key 5 with all other keys normal. Relay energizes upon the operation of key 10 as has already been explained. Relay 15, upon energizing, closes the circuit of relay 101, which may be traced from ground, through the upper winding of relay 101, conductor 51, spring 87 and its break contact, conductor 723, spring 33 and its make contact, the tip of plug P and jack J conductor 449, impulsing springs 813,
conductor 450, through the ring of jack J and plug P, to spring 32 and its break contact, conductor 60, spring 216 and its make contact, conductor 40, through the lower winding of relay 101 to battery. Relay 101 energizes and at spring 100 and its make contact closes a circuit from ground through the winding of relay 103 to battery, and at spring 163 opens the impulse circuit. Relay 103 energizes and at spring 104. prepares the impulse circuit which will be explained later. The operation of key 5 closes a circuit from ground through the lower winding of relay 102, conductor -19, spring 23 and its break contact, spring and its make contact, normally closed contact to key 1, conductor 72, through the impulse control springs of the calling device 1, conductor 71, through the break contacts of key 3", conductor 82, through spring 21 and its make contact, through spring 22 and its break contact, conductor through the upper coil of relay 102, to negative battery to ground. Relay 102 energizes and closes the circuit to relay 101, as has been previously described. \Vhen the calling device 1 is operated impulse springs open and close the circuit of relay 102 causing it to impulse over the impulse circuit to the director, as has also been previously described. By manipulation of the calling device the attendant is able to set up a telephone number on the registers of the director, which translates the number and at the proper time starts impulsing the above traced circuit to relay 101. Relay 101 falls back with each impulse and closes the circuit from ground to spring 39 and its make contact, spring 21 and its break contact, conductor 50, spring 163 and its break contact, spring 101 and its make contact, conductor 55, spring 9 and its break contact, spring 11 and its break con tact, through relay 18 to battery to ground, and also over conductor 67, wiper 170, conductor 137, magnet to battery. Relay 1% energizes over the above circuit and remains in an operated position thrmighout the i111- pulsing because of the slug on the heelv end of the core. Magnet 115 follows the impulsing, advancing its register in accordance with the first digit sent out by the director. When relay 101 falls back, it also opens the circuit of relay 103 at springs 100. However, relay 103 is a slow to release relay and remains in operated position during the impulsing.
Relay 18, upon energizing, closes a circuit, ground through spring 44 and its make contact, through the coil of relay 19 to battery. Relay 19 energizes and at spring 4:) prepares the circuit to the register control magnet 113. The circuit, however, is held open at spring 4 1 by relay 18. \Vhcn the director has finished sending the first digit of the translated telephone number, spring 850 ion closes with its make contact and shunts, out the impulsing springs 813 as is explained in the application of reference. Relay 101 comes to restenergized, and at 163 opens the circuit oi. relay 18 which falls back after a brief interval, opening the circuit of relay 19 and closing the circuit from ground through spring 44 and its break contact, spring 45 and its make contact, conductor: 58, through magnet 113 to battery. hlagnet 113 energizes and advances the wipers 170 to the second contact in connection with conductor 13S and magnet 116. .Relay 10, which remained operated for a briet' timc after its circuit was opened because of the copper slug on the heel end of the core, finally falls back and at spring 45 opens the circuit ust traced to ,inagnct 11 3. The sec-- ond digitsent out by the dire r is there-- fore registered on the second register by megnet 116, the performance being the some as just described.
\Vhen the director has finished sending the last digit it cuts itself oil and restores to normal in the well known manner, places a ground on the impulse wire which closes the circuit from ground on conduct-or 452 through the ring of jack J and plug 1 spring 11 and its break contact, sprmg 9 and its break contact, conductor 81, spring 40 and its make contact, conductor 65, spring 35 and its break contact, conductor 59, spring 160 and its make contact, spring 161 and its make contact, conductor 52, spring 41 and its make contact, through the upper Winding of relay 17 to battery. Relay 17 energizes and at spring'48 closes 21611131111) through the Winding of relay 16 which energizes without effect at this time. Relay 17 also closes a circuit through spring 86 and its make contact, to the signal lamp 64, causing this lamp to lightsteadily, to notify the attendant that the director has cut through. y
The number which the director has sent out is new registered on the test setregisters 115424, inclusive, and may be read directly oil of these registers. To release these registers the attendant operates key 172 WVlllC-ll closes a circuit from ground, through the make contact of key 172, conductor 136, to register release magnets 125 and 126 to battery, also to relays 127 and 128 in series to battery, and so on through the series parallel arrangement of the register release magnets. The director is released by restoring the key to normal. Key 10 at spring 27 interrupts the previously described circuit for relay 15, which falls back, and at springs 36 and .37 interrupts the previously traced circuit for relay 101. Relay 101 restoresand at sprmg 166 opens the circuit of relay 103 which restores after a brief interval, and at springs 167 and 164 prepares the release circuit for the release magnet 114 oftheregister control BC. The register control is then restored to normal by operating the dial release key 4 which opens the previously traced circuit of relay 102, which falls back closing the circuit traceable from ground, through spring 162 and its break contact, through spring 160 and its break contact, relay 104 having fallen back when its circuit was opened at relay 162 as previously explained, conductor 53, through spring 39 and its break contact, through spring 24 and its break contact, over conductor 50, through spring 163 and its break contact, through spring 164 and break'contact, through springs 167, over conductor 148, through springs 165, through the winding of release magnet 114 to grounded negative battery. The registers and reg ister control 01" the testing equipment and the registers of the director are then all returned to normal, ready .to check the next number which ,is set up by the calling device in the foregoing manner.
he pulsing relay 102 and the switch mechanisms 168 and 169 of the test set are used as standards against which the pulsing relays and mechanisms of the director selector and director are checked. It is therefore-necessary that these pieces of testing equipment should be frequently tested to make sure that their adjustment is standard.
l1. 1. LS
For this purpose I have provided circuit,
arrangen'ients enabling the attendant toap ply the standard routine test to his testing equipment.
To vary the pulsing relay 101 of the testing equipment, the attendant inserts TP into test jack TJ and operates keys 6 and'lO to position A and key 9to position A. Circuits are then completed from ground through spring 27 and its make contact, conductor 7 6, through the coil of relay to grounded battery. Relay 15 operates and prepares the impulsing circuit which will be hereinafter explained. A circuit is also closed from ground to the upper winding of relay 101, conductor 51, spring 23 and its make contact, conductor 67, through the test jack and plug to conductor 60, through the varying machine to conductor 61, through the testplug and jack to. conductor 68, spring 22 and its make contact, conductor 48, throughthe lower winding of relay 101 to battery. By manipulation 01": the keys K and K of the varying machine 80, pul ing relay 101 can be made to pulse with light or heavy impulses. The pulsing circuit of relay 101 may be traced from ground through spring 89 and its make contact, spring 24 and its break contact, conductor 550, spring 163 and its break contact, spring and its make contact, conductor 55,
spring 9 and itsmake contact, spring 38 and its make contact, conductor54, spring 56 and its break contact, through relay 106 and magnet 105 to battery. Relay 101 pulsing over the above circuit operates mechanism 168 in the well known manner explaincd hereinbet'ore. T impulse the mechanism 169, the attendant restores key to normal thereby releasing relay which restores, and operates key 11 to position A. The impulsing circuit of relay 101 is then traced from ground to spring 162 and its break contact, spring 160 and its break contact, conductor 53, spring 39 and its break contact, spring 24. and its break contact, conductor 50, spring 163 and its break contact, an and its make contact, conductor 55, spring 9- and its break contact, spring 11 and its make contact, conductor 56,
spring 15 1 and its break contact, to relay and magnct109 to battery to ground. Switch mechanism 169 then operates in the well known manner.
To test the impulses from the impulse relay 102, the attendant restores key 6 to normal, thereby connecting the relay to the varying machine 80 over a circuit which has been previously traced; and by operating key 13 diverts the impulses into the impulse recording mechanism 79 over a circuit which may be traced from ground through spring 162 and its break contact, spring and its make contact, conductor 59, spring 35 and its make contact, conductor 78, to groimded battery in the impulse recording mechanism 79.
To test the digit registers 115424, inclusive, the attendant connects the pulsing relay 101 to the varying machine in the manner just described, restores key 9 and key 11 to normal, operates key 10 to position A to close the previously described circuit to relay 15 thereby completing the pulsing circuit of relay 101 which may now be traced from ground through make contact 39, to break contact of key 7, conductor 50, spring 163 and its break contact, spring 18-1 and its make contact, conductor 55, spring 9 and its break contact, spring 88 and its break contact, through relay 18 to ground and battery, and also over conductor 57 through wiper and its first contact, conductor 137, through magnet 115 to battery. Relays 18 and 19 and magnet 115 function in the manner previously described to set up the registers 115-424, inclusive, in order from the, impulses of relay 101.
Having described my invention, what I consider new and desire to have protected by Letters Patent will be pointed out in the appended claims.
lVhat is claimed is:
1. In a telephone exchange, a plurality of trunk circuits containing relays, a plurality of digit translating devices common to said trunk circuits, a testing mechanism, means for connecting said testing mechanism to said trunk circuits, means for connecting said trunk circu ts with one of said translatinc devices. and. means tor disconnecting the connected translating device and subst tuting the test mechanisn'l therefor.
2. In a telephone exchange, a plurality of trunk circuit-s containing relay a plurality ol 'l,ran1= 'lating devices common to said trunk circu'ts, means for associating one oi said devices with a trunk circuit, testing mechanism, means for associating said test mechanism with the input and output circuits f said trunk circuits and for dissociating sa d translating device therefrom, means in said test mechanism for transmitting impulses to the relays of said trunk circuit under varying conditions, and means in the test mechan'sm responsive to impulses of direct current transmitted by said trunk circuit rclavs.
3. In a telephone ()It'ill:jl ff(, a plurality of trunk circuits containing relays, a test n'iechanism containing; two switch mechanisms,one adjusted to operate on a light impulse, the other adjusttal to operate on a heavy impulse, means for associating said test with said trunk circuit relays and for impuls'ng said relays. means for directing the inmulses delivered by said relays to operate one of said switch mechanisiim. and means for disconnecting said switch mechanism and for directing the impulses to the other said switch mechanism.
4;. In a telephone exchange. a pluralitv ot digit translating devices common to and coutrolled by a plurality of trunk circuits contaming relays, a test mechanism, means for connecting said test meehanisn'i to said translating device in lieu of said trunk circuits. and means in said test mechanism for then controlling said translating device.
5. In a telephone exchange. a pluralitv oi translating devices, said devices I having means for registering a. telephone number. translating it into fewer or more digits and retransmitting the translated number. a test mechanism containing relays and registers. means for a iciatiug said test mechanism with one of said translating devices. means 101' causing said test mechanism l'cltlVs: to impulse into said trandatin r device, and means for causing the translated telephone number sent out by said translating device to be intercepted and registered upon said test mechanism registers.
(5. In a telephone exchange, a plurality of translating devices containing switch mechanisms, a test mechanism containing relays. means for connecting said test n'icchanism to one of said translating devices so that impulses delivered by one of said test mech- 511125111 relays directly controls the switch mechanisms of said translating device. and means for operating said test mechanism rclays under varying conditions.
7. In a telephone exchange,,a pluralitypf translating devices arranged to register, translate and retransmit a telephonenumber and containing an impulsing device,a test mechanism containing a plurality of digit registers associated with, a control switch, means forconncctingsaid test mechanism to anyone of said translating devices, said test mechanism comprising a relay responsive to the impulsesot a' digit sent by said impulsing device for actuating onept' ,said 13egisters, and means acting at, the end of said digit for moving said control switch toassociate saidrelaywith the next register, said relay thereafter operating that register responsive to the impulses of,the :nextdigit sent by the impulsing device.
-8. 1n a telephone exchange, a trunk circuit containing relays, a translating device associated with said-trunk circuit, said trans lating device containing switch mechanism controlled by said trunkcircuit relays, a test mechanism containingrelaysand a plurality of switch mechanisms, means, for connecting saichtest mechanism with, either said trunk circuit or the translating device,means in the test mechanismfor impulsing either said trunkcircuit or test mechanism relay, means in the one instance for directing the impulses deliveredby the trunk circuit relaysto their test set switch mechanismg and means in another instance for directing the impulses delivered by said testset relaysto cause them to operateeither said testswitch mechanism or said translating device. switch mechanism,
9. In a telephone exchange, a plurality of trunk circuits containing relays, a plu rality of translating devices common to said trunk circuit, means-for associating oneof said devices with a ,trunlrc-ircuit, testing mechanism, and means forassociating, said test mechanismawith the input and, output circuits of said trunk circuit and for dissociating said translatingdevice therefrom, said means cooperating with said trunk cir cuit relays to render the disassociated translating device unselectable from other trunlc circuits.
10. In a telephone exchange, a trunk cir cuit containing relays, a test mechanism containing relays, a plurality of switch mechanisms and an impulse recording device, means for connecting said test mechanism with the input and output circuit of said trunk circuit relays, means in the testing mechanism for impulsing either said trunk circuit or test mechanism relays, means in one instance for directing the impulses from said test mechanism relays to said switch mechanisms, and means in another instance for directing the impulses from said trunk circuit relays to either of the switches of the test mechanisms or to an impulse record in device.
1. T311 a telephone exchange, a translating device containing switch mechanisms and \viththe input and output circuits of said.
translating device, means in the test mechanism for impulsing saidrelays, means for directing the impulses from said relays to operate, said, switch -mech anis1ns of either the testing mechanism or the translating device, and means for directing the impulses from said impulsing device of the translating device either-to the switches of the testing mechanism or to the impulse recording device.
12. In a telephone exchange, a translating device having means for registering, trans,- lat-ing and retransmitting a telephone numher, and means for thereafter disconnecting itself, a test mechanism containing relays, registers and a signal, meansfor associating said testing mechanism with the translating device, means for causing said testing mechanism relays to impulseintolsaid translating device, means for intercepting the telephone number sent out by said translating device and registering it upon said testing mechanism registers, and means for operating said signal when said translating device disconnects itself, V
13. In a telephone exchange, a trunk circuit,a translatingdevice, a switch train, means for extending said trunk circuitto said translating device, means for thereafter switchingthrough said trunk circuit to said switch train and disconnecting it fromsaid translating device, a testing mechanism con taining a signal, meansfor associating said testing mechanism with said trunk circuit, means in the testing mechanism for operating said switching through means, and means for flashing said signal if the switching through means operates properly.
14. In a telephone exchange, a trunk circuit, a switchtrain, a translating device, means forconnectingrsaid trunk circuit-,to said, translating device, a device in said trunk ,cir cuit fer disconnecting said translating device and switching through ,said trunk circuit to said switch train, means in said translating device-for controlling the switching through device of the trunk circuit. testing equipment, means for connect ing it to either the trunk circuit or the translating device, said testing equipment including means for operating said switch through device, means for causing said translating device to operate its switchthrough control means, and means for supervising said operations.
15. In a telephone exchange, a trunk circuit, a translating device, means for connect ing the trunk circuit to the translating device, means in said trunk circuit for lnealring the established connection, means in said translating device for controlling said disconnect means, testing equipment, means for connecting it to either the trunk circuit or the t 'anslating device, means in said testing equipment for controlling said disconnect means of the trunk circuit, means for causing the translating device controlling meanstto function, and means for supervising the operation of the disconnect and controlling means.
16. In a. telephone system, a trunk circuit, translating equipment connected thereto, a relay for disconnecting the two, a device in the translating equipment for operating said relay at a delinite time, testing equipment, said test-ing equipment having access to both the trunk circuit and the translating equipment, means in the testing equipment for causing the operation of said relay or the operation of said device, and means in the testing equipment for indicating the correct or incorrect functioning of said device or relay.
17. In a telephone system, a trunk circuit having a translating device associated therewith, that translating device having means responsive to digits of acalled number transmitted from the trunk circuit for translating and retransmitting said digits, testing equipment, and means for connecting it to said trunk circuit or translating device, said testing equipment having means for intercepting the impulses delivered either from the trunk circuit or from the translating device and for observingor registering said impulses.
18. In a telephone system, a trunk circuit having a translating device associated therewith, said translating device having means responsive to digits of a called number trans.- mitted from the trunk circuit for translating and retransmitting said digits, testing equipment, means for connecting it to said trunk circuit or translating device, said testing equipment having means for transmitting impulses of different character ,to the trunk circuit or to the translating device, and having also means for intercepting the impulses delivered either from the trunk circuit or from the translating device and for observing or registering said impulses.
19. In a telephone system, a trunk circuit, a translating device associated therewith including means responsive to impulses from the trunk circuit for translating and retransmitting the digits of a called number, testing equipment including impulse transmitting devices, impulse recording devices and switch mechanism, means for connecting the testing equipment either with the trunk circuit or the translating device. and a set of keys in the testing equipment certain of which connect the transmitting devices with either the trunk circuit or the t'anslating device and others of which connect the impulse recorder or the switch mechanism with either the trunk circuit or the translating device.
- 20. In a telephone exchange, a plurality of trunk circuits containing relays, a plurality of translating devices, common to and select able by said trunk circuits, means for associating one of said devices with a trunk circuit, testing mechanism, means for associat ing said testing mechanism with ,the input and output circuits of said trunk circuits, and for dis-associating said translating device therefrom, said means cooperating with said .trunk circuit relays to render said disassociated translating device unselectable by other trunk circuits, means in said test mechanism fortransmitting impulses to the relays of said trunk circuit under varying conditions, and means in the test mechanism responsive to impulses transmitted by said trunk circuit relays.
21. In a telephone exchange, a plurality of trunk circuits containing relays, a test mechanism containing a plurality of devices each adjusted to operate on different types of impulses, means for associating said test mechanism with said trunk circuit relays and for impulsing said relays, and means for directing the impulses delivered by said relays to operate said devices.
In witness whereof, I hereunto subscribe my name this 4th day of Oct, A. D., 1924.
FRED T. MADSEN.
tit)
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US743660A US1679316A (en) | 1924-10-15 | 1924-10-15 | Testing equipment for automatic telephone systems |
GB15724/25A GB241521A (en) | 1924-10-15 | 1925-06-17 | Improvements in or relating to telephone systems |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US743660A US1679316A (en) | 1924-10-15 | 1924-10-15 | Testing equipment for automatic telephone systems |
Publications (1)
Publication Number | Publication Date |
---|---|
US1679316A true US1679316A (en) | 1928-07-31 |
Family
ID=24989649
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US743660A Expired - Lifetime US1679316A (en) | 1924-10-15 | 1924-10-15 | Testing equipment for automatic telephone systems |
Country Status (2)
Country | Link |
---|---|
US (1) | US1679316A (en) |
GB (1) | GB241521A (en) |
-
1924
- 1924-10-15 US US743660A patent/US1679316A/en not_active Expired - Lifetime
-
1925
- 1925-06-17 GB GB15724/25A patent/GB241521A/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
GB241521A (en) | 1926-09-17 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
USRE22475E (en) | Telephone system | |
US2202392A (en) | Quotation system | |
US2506730A (en) | Private branch exchange trunkhunting connector switch circuit | |
US1679316A (en) | Testing equipment for automatic telephone systems | |
US2264052A (en) | Automatic quotation system | |
US2088942A (en) | Quotation system | |
US2370239A (en) | Special service telephone system | |
US1870997A (en) | Printing telegraph exchange system | |
US2143971A (en) | Telephone system | |
US2172579A (en) | Key sender | |
US2623956A (en) | Telephone test selector | |
US2091541A (en) | Telephone system | |
US1916760A (en) | Telephone exchange system | |
US2866003A (en) | Automatic toll ticketing system | |
US2732442A (en) | murray | |
US2748194A (en) | Drop-back selector | |
US2222099A (en) | Telephone system | |
US1340935A (en) | Telephone-exchange system | |
US1648031A (en) | Party-line automatic telephone system | |
US1612014A (en) | Recording mechanism | |
US1659832A (en) | Testing equipment for automatic telephone systems | |
US2105898A (en) | Telephone exchange system | |
US1624422A (en) | Dial-testing circuit | |
US1543933A (en) | Testing device for telephone-exchange systems | |
US1133373A (en) | Subscriber-controlled switching apparatus for telephone-exchange systems. |